Ublox SARA-N210, System Integration Manual

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SARA-N2 series - System Integration Manual
UBX-17005143 - R06 System description Page 10 of 82
1.4 Operating modes
SARA-N2 series modules have several operating modes. The operating modes defined in Table 4 and
described in detail in Table 5 provide general guidelines for operation.
Figure 2 describes the transition between the different operating modes.
General Status Operating Mode Definition
Power-down Not-Powered Mode VCC supply not present or below operating range: module is switched off.
Normal operation Deep-sleep mode Module processor runs with internal 32 kHz reference; lowest current consumption
Active-Mode Module processor runs with internal 38.4 MHz reference.
Connected-Mode Module processor runs with internal 38.4 MHz reference; data
transmission/reception or signaling activity with the network enabled.
Table 4: Module operating modes definition
Mode Description Transition between operating modes
Not-Powered Module is switched off.
Application interfaces are not accessible.
When VCC supply is removed, the module enters not-powered
mode.
When in not-powered mode, the modules can be switched on
applying VCC supply (see section
2.2.1 ) so that the module
switches from not-powered to active-mode.
Active
Module is switched on with application
interfaces enabled or not suspended: the
module is ready to communicate with an
external device by means of the application
interfaces. The module enters active mode from not-powered mode by
applying VCC supply (see section
2.2.1 ).
Then, the module automatically switches from active to
deep-sleep mode whenever possible or switches to connected
mode in case there is any data to transmit or receive.
Deep-sleep Only the internal 32 kHz reference is active;
the RF section is completely disabled. This is
the lowest current consumption mode.
The UART interface is still completely
functional and the module can accept and
respond to any AT command.
All the other interfaces are disabled. If a
trace is active on the secondary UART, it is
automatically suspended when the module
enters this mode.
In this mode the module is not able to
receive any down-link message or data
from the network. To do so, the module
must be in the active or connected mode.
The module automatically enters deep-
sleep mode whenever possible after a
network dependent time of inactivity. The module automatically switches from active mode to deep-
sleep mode whenever possible.
The module wakes up from deep-sleep to active mode in the
following events:
 Automatic periodic monitoring of the paging channel for
the paging block reception and periodic tracking area
update (TAU) according to network conditions
 A send-data request is issued to the module using the
related commands (for more details, see the SARA-N2
series AT Commands Manual
[3] and the u-blox NB-IoT
Application Development Guide [4] ).
Connected The module is transmitting/receiving data
to/from the network.
Both internal references at 32 kHz and
38.4 MHz are active. When a data connection is initiated, the module enters
connected mode from active mode.
Connected-mode is suspended if Tx/Rx data is not in progress.
In such cases the module automatically switches from
connected to active mode and then the module automatically
switches to deep sleep mode whenever possible. Vice-versa, the
module wakes up re-entering connected mode upon resume of
RF Tx/Rx activity.
When a data connection is terminated, the module returns to
the active-mode and then the module automatically switches to
deep sleep mode whenever possible.
Table 5: Module operating modes description